Experts: Urban sprawl destroying world's firefly habitats

BAN LOMTUAN, Thailand -- Preecha Jiabyu used to take tourists to see the banks of the Mae Klong River aglow with thousands of fireflies.

These days, all he sees are the fluorescent lights of hotels, restaurants and highway overpasses. He says he'd have to row a two miles to see trees lit up with the magical creatures.

"The firefly populations have dropped 70 percent, in the past three years," said Preecha, 58. "It's sad. They were a symbol of our city."

The fate of the insects drew more than 100 entomologists and biologists to Thailand's northern city of Chiang Mai last week for an international symposium on the "Diversity and Conservation of Fireflies."

They then traveled Friday to Ban Lomtuan, an hour outside of Bangkok, to see the synchronous firefly Pteroptyx malaccae -- known for its rapid, pulsating flashing that look like Christmas lights.

Yet another species imperiled by humankind? The evidence is anecdotal, but there are anecdotes galore.

From backyards in Tennessee to riverbanks in Southeast Asia, researchers said they have seen fireflies -- also called glowworms or lightning bugs -- dwindling in number.

No single factor is blamed, but researchers in the U.S. and Europe cite urban sprawl and industrial pollution that destroy insect habitat. Artificial lights also could be a culprit, disrupting the intricate mating behavior that depends on a male winning a female with its flashing backside.

There are some 2,000 species and researchers are constantly discovering new ones. Many have never been studied, leaving scientists in the dark about the potential threats.

"It is like a mystery insect," said Anchana Thancharoen, who was part of a team that discovered a new species Luciola aquatilis in Thailand.

The problem is, a nocturnal insect as small as a human fingertip can't be tagged and tracked like bears, and counting is difficult when some females spend most of their time on the ground or don't flash.

But with little money and manpower, experts are turning to volunteers for help. Web sites like the Citizen Science Firefly Survey in Boston encourages enthusiasts to report changes in their neighborhood firefly populations.

Scientists acknowledge the urgency to assess fireflies may not match that of polar bears. But they insist fireflies are a "canary in a coal mine" in terms of understanding the health of an ecosystem.